Titan Aero Drive gear and bearing alignment

Hi I just received new Titan Aero but after build parts together I am disappointed. It looks like hobbed gear and counter-bearing is not aligned as in documentation and there is no way how to align it. Is it normal or have bad piece?

Hi I just received new Titan Aero but after build parts together I am disappointed. It looks like drive gear and counter-bearing is not aligned as in documentation and there is no way how to align it. Is it normal or have bad piece?

I found another photo in our 3d printer facebook group. It is the same problem. If you look at the filament path, you will see hobbed gear and filament/bearings not aligned. Can anybody from E3D share some info about this issue?

Staff Member

Thank you for bringing this up. There are two possible reasons for this:

The pinion gear is not aligned with the black gear: check that the two faces are flush when assembling the Titan.

The black gear was not pressed in correctly when assembled here at E3D: we are currently investigating the issue and checking the QC procedure.

In either case, the misalignment should not hamper performance too much if you are using 1.75mm filament. If you want a quick fix, you can try offsetting the black gear back by however much the filament path is off. Just lightly tap the rear of the hobb (the short side) with a hammer while holding the gear in/on a vise.

If this turns out to be an error on our side, we will send out replacements to any customer experiencing issues with their Titan due to a misaligned filament path.

Staff Member

Happy that it worked out. The cause has been identified. We have recently moved the "pressing" location, and in the move it seems that the tool was offset. Now to correct all the gears that we have in stock...

Staff Member

It would be great to write some blog post how to solve it and send it to other customers. Btw I have another issue with scratched nozzle and support@e3d-online.com isn't very responsive

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Hi Martin,

this is my fault, I was waiting to see that this was resolved here first I will reply via email today however looking at the pictures the majority of the scratches around the hex wont cause any issues there is one scratch on the nozzle flat that could cause issues so I have arranged for a replacement to be sent. Sorry for the delay.

I noticed the same issue on mine. But I see that the filament pretty match slides in the correct position while printing and does not seem to affect it. I only raised a bit the stepper current due to missing steps. I wonder if this issue was really the cause to start with...

As far as I see it, the idler and hot end guides are aligned. Only the teeth of the hobbed shaft are off. Isn't this a machining error, the teeth being machined by approx. 2mm offset to the motor side? And could be also the cause of bearings shattering, because of the force caused by the filament not pushing perpendicular to the bearing axis? One bearing shattered to pieces with less that 2 spools of filament trough the extruder.
That being said, correct me if I am wrong, please, and because the hobbed gear sits flush on a bearing at each end, how moving the black toothed gear on the shaft will change anything but the alignment with the motor shaft gear?
I have the same issue on my titan aero and I would very much being able to correct it the right way.

Hi, I purchased an Aero in May, and have been struggling with the unaligned teeth on the hobb shaft, as my extruder assembled the same as Euter had pictured at the beginning of the thread.

I wasn't sure what moving over the gear is supposed to accomplish, but I did try the fix suggested in the thread to tap the black gear placement over, but that has only made the extrusion problem worse.
The hobb teeth are not in line with the filament guide below into the heat break nor the idle lever guide. Moving the gears around doesn't change the alignment of the teeth on the fixed length metal shaft..

Attached Files:

I have an aero in front of me and while this may seem like a lot it's most likely not an issue.

There's a couple things we should look at to get it as tight up as possible. To start with we need to make sure the gear is almost flush with the face of the motor. Not so close it rubs, but not much higher than that.

Then we need to make sure the mount is at a minimum of 2mm. More is better usually. Looks like you're using the stock mount so that shouldn't be the issue.

When you get the lever arm as flat and close as possible it will still appear as though the center of the inlet is off from the center of the hobb, but that's not really a big deal. This is why calibrating your extruder is so important because a little bit off can be adjusted for easily and will stay consistent.

I'm not so concerned that the notch on the lever isn't centered on the hobb, but am concerned that the filament is not following a path along the middle (or at least the flat part) of the hobb. I have calibrated the extruder so it is extruding properly/consistently; however I am still having extrusion problems that all seem to stem from problems originating around this one part.
1. Broken bearing in heat sink. After determining filament grinding was not due to clog or the ABS filament not having sufficient tension to hobb, I discovered the bearing to be broken. After reading others with same problem, I believe this is due to pressure from filament not traveling perpendicularly against the hobb.
2. Not properly constrained path. I am now printing TPU, but I find the filament is making it's way out of the hobb/heatbreak guide. Since the filament is traveling along the edge of the teeth, it has more possibility to squish about due to its flexible nature and has the chance to bend and catch on the plastic guide instead of always entering the guide into the heat break. This is pretty disappointing to me, because I purchased this extruder since it boasted a short constrained path better for flexibles. I believe if the filament could travel the middle of the teeth it would eliminate this problem since it wouldn't have the chance to slip out and bunch around. (Note, I am using zero retraction so bunching problems cannot be a result of this.)

Right now my conclusion is that the teeth on the hobb are not cut at the correct placement (too close to black gear), or one of the bearings that aligns this part is throwing off the placement (note: replacing bearing heat sink didn't change alignment).

That does look a bit out of tolerance. The stack on this thing is actually kinda crazy considering. It probably won't make a difference but be sure the bearing that's pressed into the plastic is fully seated and flush.

For the hobb I measured ~2mm below the hobb, ~4mm of hobb width, then ~4mm to the chamfered edge. Let's see if they have a drawing that can validate this. I can't tell from the picture if yours is far off or not. Maybe the plastic funnel bit could go back a bit more? Just guessing here.

As far as I can tell both the bearings feel flush, so it seems less likely that is a problem.

I do see there are some drawings of the assembly, but they lack measurements for this part. I did try to carefully measure my hobb part, and it seems mine might be .5 mm closer to the large gear than yours. See this image for measurements (I measured the right most point from the edge of the nurl under the gear and not the gear.)

There doesn't seem there is play in the funnel thing the PTFE liner is in, only one position the assembly can go into. I did take a picture with that plastic piece taken off, it's easier to see the alignment of the teeth to where the filament path would be. It's close, but not totally aligned. Looking at it like this doesn't seem so bad, but the flexible filament must be catching on the funny shape of the black piece for it to fall off the teeth.